Test Method for Determining Femoral Head Penetration into Acetabular Components of Total Hip Replacement Using Clinical Radiographs

SummaryThe aim of this pilot study was to define the mechanism and mode of polyethylene wear in acetabular components retrieved from seven dogs following therapeutic total hip replacement. The articular surface of each acetabular component was examined using contact profilometry and scanning electron microscopy (SEM). Peak-tovalley distance (P-V) and arithmetic average surface roughness (Ra) were calculated for each quadrant of the surface. Deformation of the regular profile of the machining lines was the least severe form of surface alteration. Randomly orientated scratches, fine tapered filaments, ripples, and coarse surface shredding were common SEM observations. Gouging of the convex surface of the cup was seen in two cases following failure of the polyethylenecement interface. Wear of the nonarticular acetabular rim suggested neck impingement in one case. P-V and Ra were significantly lower in the craniodorsal zone, compared to the average roughness of the other three quadrants (p < 0.05). Abrasion, adhesion and fatigue were the principal mechanisms of polyethylene wear, and were implicated in the production of polyethylene particulate debris. Meticulous removal of abrasive third bodies at the time of surgery, and correct orientation of the acetabular component, should reduce early and severe wear.Polyethylene wear is inevitable following metal-on-polyethylene total hip replacement. In this study, the nature of polyethylene wear in retrieved canine acetabular components was defined, using contact profilometry and scanning electron microscopy. Abrasion, adhesion and fatigue were the principal mechanisms of wear, and were implicated in the production of polyethylene particulate debris.

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Malunion of the Acetabulum Treated by Intra-articular Buttress

Case Reports in Orthopedics ◽

10.1155/2020/8361690 ◽

2020 ◽

Vol 2020 ◽

pp. 1-3

Author(s):

D. Saragaglia ◽

J. Gaillot

Keyword(s):

Femoral Head ◽

Total Hip Replacement ◽

Clinical Result ◽

Hip Replacement ◽

Surgical Indications ◽

Total Hip ◽

Original Technique ◽

Head Fragment

Acetabulum malunions are extremely difficult to treat, and for many years, surgical indications have been dominated by total hip replacement. We treated a protruding acetabular malunion, 20 years ago, using an intra-articular buttress, by means of an allograft corresponding to a femoral head fragment which had been cryopreserved. The radiological and clinical result with this extended follow-up is quite remarkable, which has motivated us to present this original technique.

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Standing Versus Supine Radiographs to Evaluate Femoral Head Penetration in the Polyethylene Liner After Total Hip Arthroplasty

The Journal of Arthroplasty ◽

10.1016/j.arth.2014.02.010 ◽

2014 ◽

Vol 29 (12) ◽

pp. 2415-2419 ◽

Cited By ~ 3

Author(s):

Masaaki Maruyama ◽

Keiji Tensho ◽

Shinji Wakabayashi ◽

Kenji Hisa

Keyword(s):

Femoral Head ◽

Total Hip Arthroplasty ◽

Hip Arthroplasty ◽

Polyethylene Liner ◽

Head Penetration ◽

Total Hip ◽

Femoral Head Penetration

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Acoustic Vibration and Mechanical In Vivo Analysis of the Hip Joint After a Total Hip Arthroplasty

ASME 2007 Summer Bioengineering Conference ◽

10.1115/sbc2007-175137 ◽

2007 ◽

Author(s):

D. A. Glaser ◽

R. D. Komistek ◽

H. E. Cates ◽

M. Mahfouz

Keyword(s):

Femoral Head ◽

Total Hip Replacement ◽

Hip Joint ◽

Hip Replacement ◽

Acoustic Vibration ◽

Valuable Insight ◽

Acetabular Cup ◽

Total Hip ◽

Resonance Frequencies

The major complications following total hip replacement (THA) are implant loosening, dislocation, instability, fracture and infection. It is hypothesized that vibration, in the range of the resonance frequencies, may cause pain, bone degeneration and fracture. A further understanding of the physical response resulting from impact during femoral head sliding may lead to valuable insight pertaining to THA failure. Therefore, the first objective of this present study was to determine if frequencies propagating through the hip joint near resonant frequencies may lead to wear or loosening of the components. Recently, studies found that femoral head sliding, often referred to as hip separation, between the acetabulum cup and the femoral head does occur, which may also play a role in complications observed with THA today, but a the effects of hip separation and the causes of its occurrence has not been studied as jet. Therefore, the second objective of this study was to determine if a sound sensor, externally attached, could be used to correlate impact loading sounds from femoral head sliding in the acetabular cup. Additional objective of this study was to develop a mathematical model that better simulates the in vivo loading conditions of total hip replacement patients using in vivo fluoroscopic and ground reaction data as input.

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